LAS VEGAS -- Pound-for-pound king Floyd Mayweather Jr. is making plans for his return to the ring.

Leonard Ellerbe, one of Mayweather's close advisers, told ESPN.com on Wednesday that Mayweather plans to fight twice in 2013, both on the Mexican holiday weekends that typically are target dates for major fights.

"Floyd has told us that he is fighting twice in 2013 with the first date being May 4 -- Cinco De Mayweather -- and the second date being Sept. 14," Ellerbe said.

"Mayweather Promotions is looking forward to these two gigantic Floyd Mayweather events in 2013, and we are in ongoing discussions with our promotional partner, Richard Schaefer (chief executive of Golden Boy Promotions) in finalizing the opponent and other aspects of the upcoming promotion."

Ellerbe said both fights would take place at the MGM Grand in Las Vegas, where Mayweather has fought his past six fights. Mayweather also lives in Las Vegas.

Ellerbe's announcement came on the same day of the final news conference promoting Manny Pacquiao's fourth fight with Juan Manuel Marquez on Saturday night at the MGM Grand.

A Mayweather-Pacquiao showdown, of course, is the fight fans have been calling for the past few years, but it has gone unmade. Both sides have been handed blame at different points in multiple failed negotiations.

Ellerbe said Mayweather told him and fellow adviser Al Haymon in a recent telephone conversation to begin planning the May 2013 fight.

"He told me and Al this is what he is doing," Ellerbe said.

Mayweather (43-0, 26 KOs), who turns 36 in February, last fought May 5, scoring a unanimous decision against Puerto Rican star Miguel Cotto to win a junior middleweight world title to go with the welterweight crown he also holds.

A few weeks after the fight, Mayweather reported to jail to serve a three-month sentence at the Clark County Detention Center in Las Vegas on a domestic abuse conviction. He served about two months of the sentence before he was released for good behavior.

Prior to facing Cotto, Mayweather had said he wanted to fight a second time in 2012, but nothing ever came of it after he was released from jail. Now, Mayweather is ready to fight, Ellerbe said.

"He's been in the gym. Floyd is always keeping his body in shape doing something because he's a great athlete and that's what great athletes do," Ellerbe said.

Mayweather's opponent and at what weight he will fight remain to be seen, Ellerbe said. Mayweather holds titles at 154 and 147 pounds. It is unusual that the sanctioning organizations have let him hold onto both. Usually, when a fighter wins a title in another weight division, he has only a few weeks to decide which to retain.

"That is still to be determined," Ellerbe said of the weight and opponent. "He is just looking to come back in two gigantic fights in 2013 and continue to show why he is the best in boxing."

Mayweather could try to make the long-awaited fight with Pacquiao should Pacquiao prevail on Saturday night, but that is unlikely for the same reasons the fight has gone unmade for years. Most recently, it has been Mayweather's demand for far more than 50 percent of the money that was a deal breaker. Pacquiao already has said he would accept 45 percent and also would undergo the random blood and urine testing that Mayweather has insisted on for him and his opponents in recent fights.

Mayweather already beat Marquez in a 2009 rout, so he is an unlikely opponent.

The most likely opponents for Mayweather are junior middleweight titlist and Mexican star Saul "Canelo" Alvarez and interim welterweight titlist Robert Guerrero, who is technically Mayweather's mandatory challenger and has been calling him out.

Alvarez and Guerrero are both with Golden Boy, which already has said it is planning on Alvarez fighting May 4. Guerrero has looked strong in two fights at welterweight since moving up in weight, including a brutal, hard-fought decision win against former titleholder Andre Berto on Nov. 24 that put him squarely in the running to land a Mayweather fight.

One possible scenario is for Mayweather to fight Guerrero on May 4, with Alvarez in a title defense on the undercard and the guarantee that he gets Mayweather on Sept. 14 if they both win.

"Floyd Mayweather has a plethora of options," Ellerbe said. "Who doesn't want to fight Floyd 'Money' Mayweather and make the most money they ever made in their career? You hit the lottery once you've become a Floyd Mayweather opponent."